@inproceedings{bc727c9d7f734f95b2b237999b6bd7b3,
title = "Molecular engineered ion exchange compounds for delivery of corrosion inhibitors and sensing environment ingress in coatings",
abstract = "In this paper, several examples are presented illustrating the use of molecular engineered ion exchange compounds for the purposes of delivering corrosion inhibitors within corrosion protective coating systems and sensing environmental changes in the coating environment that may be a prelude to substrate corrosion. To illustrate delivery of a corrosion inhibitor, the use of Ce 3+-exchanged sodium bentonite is presented. The extent of release is found to be characterized best by a Freundlich isotherm. Ce 3+ concentrations of several hundred ppm are developed when aqueous chloride solutions are equilibrated with the exchanged pigment. Ce 3+ released from the pigment is found to have a modest inhibiting effect on cathodic kinetics of Al alloy 2024-T3 in potentiodynamic polarization. Coatings formed by dispersing the Ce-exchanged pigment into an epoxy resin are also modestly protective. Scribe corrosion is not inhibited, but propagation of blistering and filiform corrosion from scribes and cut edges is inhibited well. A method for assessing the extent of Ce 3+ release by careful characterization of x-ray diffraction patterns generated from the pigment in the coating is described. The ability to sense the extent of inhibitor release, may be useful in determining when a coating needs to be replaced. In the second part of the paper, the use of a specially prepared anion-exchanging hydrotalcite compound for potentiometric sensing of chloride is discussed. The sensing method is based on the clay modified electrode approach and results in electrodes that are sensitive to changes in chloride ion concentration over 4 orders of magnitude. An experiment demonstrating how this approach can be used to embed sensing electrodes in coatings is also described.",
keywords = "Aluminium corrosion, Bentonite, Cerium, Corrosion inhibition, Hydrotalcite, Ion exchange compound, Organic coatings",
author = "Buchheit, {R. G.} and S. Chrisanti and Ralston, {K. D.}",
year = "2007",
language = "English",
isbn = "9781622762439",
series = "47th Annual Conference of the Australasian Corrosion Association 2007: Corrosion Control 2007",
pages = "657--667",
booktitle = "47th Annual Conference of the Australasian Corrosion Association 2007",
note = "47th Annual Conference of the Australasian Corrosion Association 2007: Corrosion Control 2007 ; Conference date: 04-12-2007 Through 05-12-2007",
}